We doing NFTs sale too with around 1,500 items and sold out because the bot sniping, on our second sale we make a different method by spreading each item. Even people can buy multiple items, I think still have some gap time maybe a couple minutes or hours if not buy by a bot.
NFT sale is literally sold out like hot cakes nowadays so its always good to get yourself a whitelisted spot on the presale. Pretty sure that Rollbit could be trying some new type of sale for Rollbot 2.0 but as long as there is a presale then Im going to get myself a spot on that
One of the reason could be that the public sale wasnt cheap compared to some other NFT project back in the days. It was $1000 but presale was $500 so thats double from the presale's price and most NFT project usually cost lower than $1000 so back then there was some doubt from members that the price might not goes up further anymore