It's no secret that bartending can be a frustrating gig. It's tough standing for hours on end, dealing with annoying drunk people and bad tippers. Sometimes things even get physical. But the most annoying part of the job is sometimes as simple as making a mojito. That's what we've learned from a particularly educational thread on the Bar Memes Facebook group. The community is a haven for service workers , a place where they can share jokes, experiences, and even ask for advice with the knowledg…