If people don't play the BF right EVERY TIME, then you really cannot blame the users for failing to play the game correctly for 7 years. Sacrificing yourself to take down half of the tank's HP, getting sniped leading the charge on the VP, repairing/positioning support weapons... There is no way to tell your piece of shit tank teammate to spare your fortifications, no way to co-ordinate against the tank with proximity chat, no way to co-ordinate any kind of combined-arms advance (air, armor, snipers, frontline) no way to communicate outside the squad, no way to ask someone to tow your AT weapon somewhere.
Also, snipers are loaded with knives. When you overload their kit with CQ tricks, it is an incentive to play the scout.