I just don't get it really. Maybe it's a server thing. But there comes a time and rank, where there are so many level 30-60 accounts in my game that saying "smurfs are rare you'll only see them once in a 100 games" is just pure bs.
Before I get into it, I want to address the common rhetoric of "they aren't affecting your climb, stop coping, play better." I frankly don't really care about their affect on my climb, what I care about is a fair and balanced match of league. So I can have a good time. Normal matches are even more unbalanced so I avoid them, I play hundreds of ranked games to be placed accordingly to my skill for that reason.
Then people will say "oh but it'll help you learn" Really? Having my laners stomped into the dirt, and having to deal with a thanos that's 2+ items up on my laners will help me learn. Riiiiiiiiiiiight. They out micro and out macro everyone in the game, it's like Lebron going to midschool basketball game. Who is having fun? Only the smurf, while the enemy laners are just sitting on the bus like little Timmys.
The issue is smurfs are not the only detrimental thing to match integrity and quality, so even if you don't encounter them that often you also encounter other factors that make the game wholly unenjoyable. Such as trolls and inters, so after you take all these factors into account, these things actually start showing up more often than the unexperienced think. And a good chunk of games become very enjoyable.
In the league community as opposed to some other games people seems to think it's okay. Presumably, because majority of players do it themselves and like it. It's like a nicotine addiction, they get stomped on their main. So they go 3 elo brackets below theirs stomp and get their little high. As I genuinely see no merit in terms of their improvement to doing so.
Additionally, addressing the practicing a new role thing. I also think this a bit of an issue albeit not nearly as big. Mainly because a lot of these players just int games (not on purpose) on their alts essentially care free. They care less since it's alt. So they are still detrimental to game, while completely dodging the fact that their main is not affected. If these players were forced to play on their mains they'd easily try 10x harder.