Mines do squad wipes, OH and OKW mines too. Rifle grenades wipe squads. You lose a squad or two in any game. But if you don't blob up too much spamming demos ain't gonna be an issue.
As I told Alex this is mostly an issue OKW blobbers face. Also OKW Strums are the only engies who can toggle their sweepers thus not losing any combat efficency.
It does punish blobbers, yes. It also punishes players who don't blob.
It punishes OKW and OH. It can't punish the allied factions (who also have plenty of blobbing) because axis don't have it.
Would you like to see your expensive elite infantry deleted one by one? Would you enjoy not being able to harrass points because there is probably demo?
I'm against blobbing but I think there are better ways to dissuade players from doing it than demo. I don't think either faction should have it. Squad delete buttons go against fun gameplay.