Well during the industrial revolution virtually none of the people who were moving into cities to work in the factories came from hunter gatherer communities.

Let's say you wanted to be a hunter gatherer in the UK during the Industrial Revolution. Where would you do it? Depending on terrain, hunter gatherers would need quite a lot of land in order to get enough food to feed themselves. If you owned that much land during the industrial revolution you wouldn't hunt to feed yourself, you'd rent out that land or sell it and you wouldn't have to work at all. If you didn't own enough land to support yourself through hunting and gathering then where would you hunt and gather? Private land? How would that work? You can't exactly set up a hunter gatherer camp in someone's garden or public parkland.

The people moving into the cities to work in factories were generally coming from farming communities. Whatever the downsides of working in a factory, rural farm labor was hardly a picnic either. Working at a tenant farmer (i.e. renting the land you were farming) involved hard work and very low income levels.

Also even if you wanted to be a poor tenant farmer that wasn't always an option. There were large increases in agricultural productivity in the 1700's in the UK which meant you needed fewer farmers to produce a given amount of food, this has only accelerated in modern times as the percentage of the population engaged in agricultural labor has steadily dropped. In addition there was the famous Enclosure Movement in which what had previously been common land (where local people could graze their dairy cows or what have you) were privatized which put landless farmers in a worse position. Also some of the farmers that were moving into the cities in Great Britain were coming in from Ireland. Factory work was bad but staying in Ireland and starving to death during the Great Hunger was worse.

Also think about what early factories were producing during the Industrial Revolution. The focus early on was often on cloth. A lot of this cloth was made with imported cotton but some was also made out of wool. This created a lot of demand for wool which meant that some large landowners switched their land over from tenant farming to sheep pasture. You need far fewer workers to herd sheep on a given area of land than you do to farm it. So if you turn a large portion of land from farmland into sheep pasture you're going to end up with a lot of unemployed people. If your landlord just kicked you out of your home in order to make room for sheep, where are you going to go? There really weren't any good options at the time, so one was working in a factory.

Your question is more or less the same as "why do a lot of people work in retail these days when retail joys have low pay an involved being shouted at by rude customers all day long." Well pretty much nobody wants to work in retail but people need to eat and when it comes to paying the bills most people need to get a job and they can't always be choosy. Modern people can't exactly quit their Wal-Mart job and go live in the woods by hunting and gathering and the same applied during the Industrial Revolution.