The score says how it ended. xG says how it should have ended: it is the sum of the chances each shot was worth, not an opinion about the game.
Lorient created more (1.07 xG against 0.96) and left with nothing.
Le Mans: +0.8 for the season (9 in the table). Lorient: −1.4 (12). The gap between points and xPTS is built from matches like this one.