The first gas stations were merely attachments to other businesses. A general store, hardware store, pharmacy, blacksmith shop etc. would also have a tank outside with gasoline. The gasoline would be poured into a bucket to measure and would then be poured into the gas tank through a funnel.

The first purpose built gas station was built between 1907 and 1909 depending on whose account you accept and how you define filling station. These stations remained largely just places to get gas with few extra services until the mid 1920's. Sinclair opened the first "greasing stations" in 1926 these provided vehicle maintenance service as well as fuel. This was in large part due to the rise of General Motors with multiple competing cars came the need for mechanics to service multiple types of vehicles. By 1929 there were 121,513 filling stations in the US according to the US census of business. Other estimates place the number of filling stations as high as 250,000. The difference between the estimates being that the US census of business only included businesses describing filling as their primary business.

To answer your question in 1922 modern gas stations didn't exist. Purpose built filling stations had limited service. Many motorists preferred to stop at the local store to buy gas and other items. Pharmacies were a popular place because they had gas as well as all the snack goodies we now associate with gas stations. During the 20's there was a meteoric rise in the number of cars on the road and this was accompanied by a rise in the number of places to service and fuel these vehicles.