The simpler answer is that when the Vandals took over North Africa, the western Roman state was still in existence and as an antagonistic entity. The rest of the empire was busy attempting to retake Africa from the Vandals throughout the course of its entire existence, until finally Belisarius pulled it off.

Compare this to both Odoacer and Ostrogothic Italy, which were nominally ruled on behalf of the (Eastern) Roman Empire, and where it was seen as a political benefit for legitimacy to show continuation with the Roman Empire, rather than antagonism against it. This of course changed after Theodoric's death, but the relative speed of the time from his death to Eastern Roman invasion provided no opportunities for the Goths to adopt and cement widespread "anti-Roman" policies, except as specific reactions to on-the-ground military circumstances.

Now with that said, one would argue despite specific non-accomodations (like Huneric's degree of heresy against non-Arians, i.e. Orthodox Roman Christianity), the bulk of political and economic framework for Vandal rule was almost entirely Roman. Even Huneric's decree is couched specifically in Roman language not unlike previous imperial decrees. Vandal administration was almost identical to the previous Roman one, including taxation and their use of coinage. Dress styles changed to accomodate the new political leadership, but the function and the ceremonial of the politics was firmly Roman.

Which in many ways, presages the developments later during the early stages of the fragmentation of the empire, where the bulk of administration and culture of the ruled populace remained quite Roman, and only the top level was there a significant cultural change.

I'm going off of class notes right now.

The simple answer is that the Ostrogoths were very familiar with Roman culture already. Trade was very common between the borders of the empire and the barbarians. Many germanic tribes served in the Roman army. However, I would agree with GeorgiusFlorentius in that the Vandals weren't there to destroy Roman culture, in anything, I would say that they kept it going. Many of the successor states can be seen as a transfer of power, from Roman rule to a Germanic one. A few Goths like Athaulf even married into the imperial family, and Stilicho, Honorius' chief minister, was half Vandal himself. They all thought they were continuing the old empire. Of course, it gets a lot more complex after the fifth century and the beginnings of feudalism, but I would largely say that things were relatively the same after the germanic "takeover." I've started to see these less as barbarian "invasions" and more of a transformation of sorts.

Some books you can check out:

Christ Wickham's The Inheritance of Rome. Peter Brown also holds the "transformation" viewpoint, you can find his book on Amazon too. And for a good Migrations period text this one was useful.

I am sorry not to have time for a more comprehensive answer, but for me, the Vandals do not seem to be any more “unaccommodating” to Roman tradition than other Germanic people of the same era. Their bad publicity comes from their representation as persecutors, and it does seem that their attitude toward orthodox Christians was less understanding that the Ostrogoths' (even though prosopography has shown that important families in North Africa had been able to retain their influence, and that there were considerable periods of respite in the persecutions). But on the other hand, if you read (for instance) Procopius' Wars, you will not get this impression; actually, he describes them as very civilised, and even as softened/corrupted by their luxurious life (see Vandals II.19) — while in the Gothic War, he mentions the Ostrogoths' warriors hostility towards the idea of giving a Roman instruction to their prince, even though it seems that many members of the royal family were actually quite educated.