For work: It is literally my job to interact with peers at meetings and conferences. Hard to get there if I have a week of travel for every conference.
For pleasure: Because the destination is worth it. And the hassle isn’t even that bad. Even without a tsa pre-check equivalent, security is mostly fine if you know what you are doing and prepare accordingly. Liquids baggy near the top of your bag. Have a jacket you can shove your phone and watch into. And so forth. Bring a book or some headphones to keep yourself entertained on the flight. Realize that you can slide your feet under your bag to greatly increase your effective legroom. And don’t hesitate to walk to the restroom, even if just to stretch a bit.
And then I get to land somewhere interesting. Whether it is visiting friends a few states over or spending a week or three in a foreign country.