it does depend on the petsmart, talked to the fishguy at one near my work. He said they get new all the time, after 30 days they start to look not so good and he moves them to a clearance area at half price. Some other stores seem to leave them in the shelf half dead and not replace the stock. He had the bags of hairgrass, microsword, etc, and 3 different size tubes of anubias, wisteria, sword, ECT. Prices are more than what most what are asking in the trading room, but you don't have to worry about shipping.
There are a lot of non aquatics, but they seem to be marking them with a green sticker now.
The clear jelly is a hydrostatic gel ( I think that's the term) that I have run into before - its used in agriculture to absorb water and release slowly, prolonging the time between watering, and in cigar storage as an alternative to a wet foam humidifier. It swells to many times its size when soaked in water