I'm lvl 23 and during my game i met a lot of gold or silver players who were premade with others under lvl 30. They have full runes and masteries and are more experienced then we. In my honest opinion it's unsportsmanlike. What would u say about?
I call it playing with friends who aren't 30 yet and it is something I myself have done in the past. For example, my friend and I used to play all the time together starting from level 1, but he quit around level 26 and obviously I've kept going. We still play from time to time together, but he's still 26 and I'm 30 with 6 rune pages lol. I have the option to play with him on a smurf....but I'm still going to have that experience you talk about. My Diamond friend is leveling his smurf and he is already at an MMR where he was playing against Golds in norms at level 23 and even with the rune page mastery deficit, he 1v5 won the game so those really don't make that much of a difference to the experienced player.
It's also worth noting that doing this repeatedly will boost their MMR so the pre-30 will end up playing with 30s more often than with other pre-30s or will be paired against smurfs. And even if they do play with you, sometimes that's the best learning experience. Ask them questions, watch their movements, learn from their builds -- I'm Silver/Low Gold MMR and I play with Diamond+ when I team up with high elo friends. I get stomped in those matches, but I've learned a ton from them.
Finally, they aren't really "boosting" their friends either in the same manner one would boost a ranked account. By winning, they will get slightly more experience, but games will probably be shorter which will lessen the experience. What they are doing is perfectly fine and by no means reportable or bannable. There is no rule against playing with friends of varying level or rank (except in ranked).
As someone who has done it from both sides, I think it was the best learning experience I had. When I started, my Silver and unranked 30 friends would play with me. I played support (I've always been a secondary attackers kinda person adn it fit with me). I realized that watching the higher level friends play helped me learn BETTER things, even if I got my rump handed to me over and over again. I learned to accept loss better and enjoy the game and when I went into games with my own level, I was able to use higher learned tactics.
While it gives a slight advantage, like Jikker said, you really cant blame people for playing with their friends. Specially when there are SO MANY utilities out there to learn better tactics and such.
