The most common and most likely answer to this crossword clue is the 11 letter word SUBURBANITE
I've seen this crossword clue in The Guardian
S
U
B
U
R
B
A
N
I
T
E
More clues leading to the result SUBURBANITE
Buddy explains!
The straight part
We know that "One has a trek to town centre" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one has a trek to town centre = suburbanite.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.