You should because that’s how tipping works. No one likes tipping (as a customer anyway, plenty of servers and owners do), but until servers are provided with a living wage that’s how it works. You’re not changing the system by tipping less - you’re just being a dick.
And not for nothing, but there is a slight difference between soda service and a simple pour service. Actual liquor service usually comes with someone asking how you like it (e.g. on the rocks vs straight vs three drops of water) whereas a soda is just a soda. Sitting at a bar, no one is gonna get pissy if you’re not tipping 15-20% on opening beers or straight pours, but that’s just how table service works.
It’s worth noting that not only did I not have to create this meme, I didn’t have to Google that hard to find it.