Bleh, yeah. Supports who don't understand how to play the support role are frustrating. Your job as a support is to make it safe for your adc to farm and make it hard for the enemy adc to farm. If they adc wants the wave pushed, let them do it. If they want it frozen, let them freeze it. The support should not be attacking the minions unless they have relic shield, which generally should only be them last hitting cannon minions or melee minions.
It just sucks when you had an support who decides to keep shoving the wave, constantly trying to engage at points where the enemy has the advantage, etc. and so the only way you can get farm is to go to their tower to get it, in which case you're over-extended, and if you die, suddenly it's "Our adc is so bad." At least it's a good feeling when you have a good support who leaves the wave alone and just zones so you can farm, and knows how to trade correctly and make sure that you're in position to trade too before they go all in. 
I understand why champions with minion collision spells like Thresh, Morgana, or Blitzcrank would want to affect the wave in order to set-up for an engage on the enemy. However, more often than not what I see is that they see the minion wave around our tower and they react defensively and start auto attacking the minion waves as if they are someone drowning under water and trying to bat at the waves with their hands as if they were trying to stay afloat.
In the same vein, if your support is someone who has trouble dodging skill shots then maybe they prefer to have that wall of minions so they can just watch their screen and stand still for a couple of seconds, rest easy for a bit. Because I know that
auto-attack closest target feature doesn't trigger unless you're really not right clicking on anything. But yeah in the case that the enemy has pushed out your wave my mentality is always to let it push while kiting back the minions.
I also understand why having a minion wave would be useful towards applying minion aggro when you want to cs and you're getting harassed by an auto. But let's be real here, I've never had anyone trade CS for harass with me in bot lane. The enemy champion could be on Caitlyn and will still be out of position to harass me when I go in for CS because she's too busy auto attacking a full health minion and pushing those minion waves hard like she's about to give birth.
Personally though I stopped playing supports that have collision oriented spells. I only really play Annie and harass the ADC out of lane with magic pen reds + AP quints and blues. And I know every time I hit Q it's going to hit them. My delayed auto motion is going to hit them. Every time I want to cc someone as Annie, I know I will cc them. Just that 100% guarantee and 100% harass all the time with people who just walk into my range and let themselves be hit. I'm even trying out Nunu with the same exact concept because he synergizes really well with a tankier build giving me a tank with guaranteed harass option (bc no one wants to play tanks in Solo Q even if it means we pretty much lose at champ select with Fizz Top, Elise JG, Yasuo Mid).
With respect to the second paragraph, in Solo Q if I tell my ADC to stop pushing and they just straight up ignore me then I just literally leave the lane when we hit tower, ward up the river, and gank mid with stun. Chances are they die in a 1 v. 2 or a 1 v. 3 if they don't back off, but the team doesn't blame me because I indicated that I was going to gank mid. The ADC keeps pushing like an idiot, then let him keep dying until he realizes that the reason they are dying is because they aren't only last hitting. Maybe a bad attitude, but I'd rather gank some assholes rather than letting myself be ganked on a non-tanky oriented champion that can't buy the ADC enough time to make it back to tower without someone dying regardless.
