Hinges are a common problem on a lot of makes.
How tight is tight ? it's very subjective.
Always try and open with two fingers splayed centrally to put equal force on both hinges... never just grap a corner and pull it open.
WD40 won't do any harm but be very careful what you use, any mineral bases oils can attack and soften plastic over time which would be a disaster.
Your best bet is probably a silcone based lube.