Sorry! I thought what you had to say in your post was more of a comment than a question.
As far as the reference to wanting your cake and eating it ... My feeling is that as your seniority improves with every year you will understand more fully why UPS/union has the transfer policy set up the way it is. If you or any employee decides NOT to transfer and you stay at the same facility and same job (let's assume it is a package driver job) you will want the protection of your building seniority so that you can continue to establish your position of the benefits that building seniority gives you. To name a few - bid rights, vacation picking and a big one LAYOFF.
How would you like to work in a retirement location such as Maui, and folks all over the US continued to transfer in with more seniority than you and you had 20 years and were picking your vacations last and had a chance to be laid off and continued to be stuck in a utility driver position because these new folks who are coming to the island kept getting the good routes?
Is that fair?
Another thing.... If it were company seniority than a person with 30 years could transfer every 6 months be the first in line to pick a vacation and bid on a route and never fear he/she would lose their job. If they didn't like the place they could go to the next operation and do it again and again.
They would be upsetting the apple cart everywhere they went and continue to gain seniority as they do it!!!! I could be wrong but I really think the majority of folks would not like their life turned upside down like that.
Not to confuse the issue but....
If you are in management it works by company seniority. The difference is that management does not get to pick and choose where they will be working and as you know...they get transferred all the time. It also goes by position and operation depending on where you are. I have seen managers with 10 years of company seniority picking vacation over their supervisor who has 20 years of seniority. Promotion has it's privileges.