If I were going, I would be looking for a village pub that does meals, that the route passes. Watching all the vehicles passing by all day is more entertaining than the 30 seconds it takes the peleton to pass by.
YesBut
There is a lot going on in a start or finish town and lots more if its both as Lille is. I haven't been to a depart town, but have been to a finish - the caravan does come through the finish too you know

, and you see all the set up and can have a walk up the last km etc.
The start you have all the sign on and presentation etc and chance to see stationery riders bikes and mechanics.
Watching the caravan and the race come thru is great too, especially if its past your front garden!