From my reading of https://www.netlify.com/pricing/#forms you will need to pay $19/month/site (!) just to collect the data from 1000 form submissions. By the time you have a couple of sites like this the price is already way too much for me and anyone else with basic backend knowledge. I hope I've misunderstood.
It's $0,019 per submission, which I think is a fair price if you're actually sending that amount (and making money from it). It would costs you much more to build unless. That said, for personal (free) use there are a lot of alternative options.
They give you the ability to have 2,000 contacts in the system at one time for free.