Using Whypark you are unlikely to get much if any traffic from search engines.
So, yes, basically the only 'real' benefit is not having to split and revenue with a parking company.
I don't have any tracking installed so i can't tell whether the visitors i've got from search engines have then gone onto click an advert.
Around 10% of my traffic is coming from search engines on my test sites.
An example of one of my homemade pages is
Optare, note the lack of any real content! However this works as a starting base, a better example would be to have a series of small articles published.
As an example (not exact figures & not for the domain above) for August i got 27 Clicks (with a CTR of 15%) earning around $12.00, for the same domain with namedrive (for its best ever month) i earnt just over $3 with a similar number of clicks (with a CTR of 11%)