DO ANY OF THE HOTEL IN BONAIRE OFFER AIRLINE DISCOUNT, AND WHAT HOTEL OFFER ALL INCLUSIVE PACKAGES

That's a broad question.
Many of the hotels and even smaller properties offer more than just room packages.
Plaza, Harbour Village and Habitat all have some sort of all inclusive plans - meals, rooms, sports/diving, airfare. Condo/apartment places like Bel-Mar, Caribbean Court, and Lagoen Hill have airfare, room and sports/diving but no meals I believe. We also have a couple B&Bs on the island for room, meals and sports. I do apologize to any property I forgot to mention.

The other option is to contact some of the dive tour operators who specialize on Bonaire and see which properties they offer.

Can I ask a question? Do any of the airlines offer the hotel and dive shop workers or managers discounts?

The airlines for sure don't...contact the hotels directly and see what happens. You may also want to contact the tour operators...email be for a list.

My wife & I and our 2 sons (13 &14) are trying to choose a place to stay on Bonaire. Thinking about Buddy Diver Resort, Plaza Resort or BelMar Apartments. We only snorkel. Any suggestionsas to which would be best?

the snorkeling by Sand Dollar is very good--there are still a lot of fish there. Buddy Dive is next door. They both suffered damage to their restaurants.
Plaza has a large beach and I'm not sure how the snorkeling is off Plaza (it is usually worse over beach areas than over coral). The diving there is fine. Staying at either Buddy Dive or Sand Dollar you can snorkel up and down the coast from Harbour Village to Capt Dons. Lots of fish to see.

Check air Jamaica...They had some package deals with plaza resort that were pretty hard to beat prior to Christmas.

I got a very good deal on an Air Jamaica flight from Caradonna Caribbean Tours 800-328-2288. Since I'm not going for another month, I can't vouch for Air Jamaica yet, but they seem to have been getting good reports.