Perlite helps keep good drainage in germination & potting soil mixes. Ideally, it is sterile, so it helps in germination by not transmitting damping off disease to seedlings & cuttings. If these bags of perlite have sat around for awhile or got wet inside, they may not be so sterile anymore.

It doesn't hurt if some perlite gets put in the ground when transplanting, but perlite really doesn't help anything either and it's not meant as a soil additive, as it has no nutrients. I mainly use it for rooting cuttings of my sages and tomatoes, mixing it 80% perlite/20% washed sand.

i know it did not get wet but its been hanging around for a couple of years. how would i get rid of it? does anybody want some?

Put it on Craigslist or leave it at the street on your sidewalk with a sign 'free'.

I wonder if you can use it to make hypertufa?

Here is a link that might be useful: Hypertufa forum

Years ago we had a free source of perlite and dug a couple of trailer loads of it into our heavy clay garden. In years after we dug in rabbit and chicken manure, so there have been lots of amendments since, but that original application of perlite made it possible to grow veggies at all. We could make pots out of the original soil!

hosenemesis, i dont think i have the patience to make hypertufa,maybe when i was younger i would have tried since i was doing ceramics 20 years ago, that would have been great,
suzannesl, i think i'll work some of it into the soil.