The baby food might provide enough water for them. If you are buying small crickets in quantities of 500 then it may not be enough. Food too may be an issue. They need a constant supply of both food and water. If you check in on them and everything is eaten, then you are not giving them enough, IMO.

Getting back to the 500 crickets....... that's a little overkill if you aren't raising your own. I don't know what the size is for a large cricket keeper, but 500 probably needs to be kept in something at least 15"Lx12"Wx12"H or bigger and they need ventilation. Temperature, though it has not been an issue for me, might be if they don't have a sufficient source of water and ventilation. Particularly during shipping or trying to get them back from the pet store and you make a stop or two for other things, leaving them in a hot car.

You only need at most six crickets per week for each FBT (again, IMO and with caveats). So if you are not raising your own, then the smallest, cheapest package you can get will be my recommendation. Also, I can't see buying crickets online as economical for a few FBT's. Crickets grow faster in hot weather, so two weeks might not always be a realistic expectation to still have a feeder size cricket for your frogs.