What are the consequences if i do the following,I have a Non O visa and have a one year extension but i am currently working abroad and only visit Thailand 3 time a year.If i do not apply for a new extension in December and just return on my 3 holidays will this affect me applying for a new Non O when i finish working.

If i do the above it will save me applying for a multiable re-entry permit 3800 Baht

You are married to a Thai? It will have no effect and for people working outside a good option is the multi entry non immigrant O visa and you have free travel for up to a year and up to 90 day stay. But if your stays are 30 days or less and you will have return ticket there will not be any need of a visa. When ready to stay in Thailand again get a non immigrant O visa (or change in country if you have the financials ready) - and proceed with the extension of stay routine again.

Edit: will add poster is from a country allowed 30 day visa exempt entry so can use them if he wants.

No short answer is no, just apply for another non-immigrant 'O' at some point in the future. Use visa exempt 30 day entries for your short Thailand visits while working abroad.