Main ways one enters bars after being intoxicated (9)

'main ways' is the definition.
'highroads' can be an answer for 'ways' (highroad is a kind of way). I am not certain of the 'main' bit.

'one enters bars after being intoxicated' is the wordplay.
'one enters bars' becomes 'roads' (I can't explain this - if you can you should believe this answer much more).
'after' is a charade indicator (letters next to each other).
'being intoxicated' becomes 'high' (similar in meaning).
'roads' put after 'high' is 'HIGHROADS'.

Can you help me to learn more?