The server I go to is militarized (1st person only) and the situation with thermal optics doesn't affect gameplay. No one complains about it because of the cost of having one.
The server features RHS and CUP so you'll see more optics/vehicles that feature thermal. With that, the owner increased the price dramatically, having it as a luxury or "bragging rights". For an example, a Nightstalker is 50,000 caps. The price puts this in your minds:
This makes me a bigger target
If I lose this, this will hurt me economically.
Is it even worth having if it cost this much?
These things go in your head because if you don't have the funds or self-esteem to use this, you will have a bad time throughout the server. I'm friends with several players who are new to ARMA. And even tell me they don't want to use expensive hardware because they don't want to take the responsibility for it. For an example, a T-34-85/T-55 features only the basics such as decent armor and night vision. The price ranges 100,000 to 200,000 caps. It's a reasonable price because of what these vehicles can do (easily destroy hunters/APC's). If you want to consider upgrading such as the T-80/90 or M1A2 Abrams, prices surges 400,000 to 500,000 caps. Reason is because of the superior weapons technology on these machines.
Of of course you're thinking, "OPOPOPOPOPOP" but it truly isn't because there's several ways to engage these vehicles. Either throw grenades at the tracks (to leave it as a sitting duck) or keep hitting it with AT missiles. On the server, only two people own the Abrams or T-90, even then they rarely use it unless it's really needed. APC's and light tanks are more common (Post ww2 or Cold War vehicles).