Most people feed one can of 5.5 oz a day, unless it's a growing kitten or pregnant mother. Two a day seems like a lot.My cats weigh about 10 lbs each, so I think that means they need two 5.5 oz cans of wet food per day, correct?
That's 4 cans of food per day at often $2 per can.
Feeding a not-so-good brand of wet is still better than feeding dry. It's not going to kill them. You have to factor in your financial ability, and as long as you're giving them a good and happy life, don't feel bad for not being able to feed them filet mignon. Many cats live long, healthy lives being fed Friskies and Whiskas. It's not the best, but don't feel like it's the end of the world.
I don't really know the price of wet food because I feed raw - I used to feed Wellness and, like you, I couldn't afford to keep feeding my one cat $2 a day (over $700 a year!). I switched to raw, which costs me about 89 cents to a dollar a day. It's an expensive upfront investment though - I have to keep feeding raw for 8 months before it becomes cheaper than feeding Wellness. But long-term it saves me a lot of money.