Yes, just quickly do the math – and you will see that people who make enough income to afford $2500 a month do not want to rent. They want to buy.
I think rents are increasing because mortgages have, and the owners need to try to get as close to their mortgage as possible. If you look closely, you see all kinds of variation in rental prices for homes of similar quality. Again – has to do with what the break-even (or at least get close to breaking even) point is for the owner.
Rents can only go as high as the local population is able/willing to pay.