Can't wait until I earn loads of money like that. I already earn quite a bit with Adsense but nowhere near that much.
There are big difference between niches and a lot depends on ad optimization... Maybe you should experiment with better placement, different colors, different offers, etc... Maybe your visitors are not in the mood to click, so getting more targeted visitors is also an option. There are several factors included.
I don't know, How's the blog can make that large money? that big traffic? where the traffic come from?
Don't know the whole story here but sounds like they were setup for failure. You had the store for 4 years...no doubt over 50% of your customers came to your store because they knew you where the owner...the little guy. Apparently they could have gone anywhere else but they didn't. Now I don't know how it went down but I would imagine if you would have brought them on board under the guise of New Employees. Had they worked a few month with you side by side...the customers would have gotten familiar with them. It would not have been such a shock to them when one day they came in and didn't see you. Matter of fact it would have been awhile before people started asking "hey is Cody sick or something?" then they would have explained that they bought you out...and business would have continued as usual. I know a lot of business that lost a lot of customers when ownership was changed!