The only people that ever think this way are the bottom feeders.
Senoirity gives privilege. Fortunately for me it's never much mattered. I've been able to get most of the vacations that I wanted for most of my 20 year career. Even when i wanted summer. This last time I took 2nd week in May, a week in June, Labor day week (last week), week of Halloween (so I can be home for Trick or Treat) and the last week in March. I spread my 5 weeks out.
If I have a lower seniority driver who I am on good terms with ask me to avoid a week so they could possibly get that week I will try and accommodate as I hardly ever have any set plans for my vacation time. But if you ask and have screwed me over before then sorry about your luck, and best wishes.