That's what I thought, until the other day I realised something I had installed was via snap. I'm afraid the only solution requires stop using Ubuntu :(
sudo apt purge snapdI haven't verified that, but considering that nothing suggested that I was installing a snap app (other than me not paying attention to apt's output, I guess), I'm not sure if that's even possible. I was planning to stay with 18.04 LTS and then move to something else, but seems like either snap was there already or it has been added after I upgraded.