Is it normal to have dental sealants on all of your teeth for life?

Yes and no: Sealants can only be used on the grooves of the back teeth. That being said, the sealants will last a long time, probably not your whole life. However, they can be re-applied if they come off. There are no sealants for the front teeth.

They do last..: Sealants are great and worth the initial expense when applied. Each dentist has his own thought on who and how many teeth get sealed. For my patients i usually only do molars unless a person does appear cavity pron or has deep pits and fissures on their premolars. Some dentist seal all posterior teeth regardless. Anterior teeth are very rarely sealed.

Highly Unlikely: It would be highly unlikely for you to have sealants on all your teeth for life.