You don't need REP to create and bet on markets in augur.
REP has value because REP holders get paid 50% of the transaction fees incurred by betters in exchange for reporting outcomes of the various events that are bet on. So REP holders get paid for helping to resolve a market.
For example, if augur sees $1 billion in betting volumes (which is trivial in the betting industry) in 1 year and the transaction fees are 1% then REP holders get $5m in total and since there are 11 million reps in existence, you get paid ~$0.45 for every rep you own.
So, in a way, if you buy REP you are basically buying a salaried job that is very very easy to do and takes almost no time.
thanks for the explanation.
so REP tokens are shares that pay dividends, and not 'gas' that power/ authenticate transactions.