For the sake of playing the devil's advocate let's take a quick look at the bright side of this type of promotion.
We'll use an example I found through Google.
The offer: $200 worth of services for $99
Total sold: ~150
Gross sales: $15,000
Businesses Cut: $7,500
So for zero invested this business gets $7,500 in hand and ~150 new customers. Each of those customers come to them with essentially a gift certificate worth $200. Is there a potential to sell a package worth more then $200? I would think so. If you impress these customers will they come back at some point? Maybe. Will they tell people they know about your business? Most likely, yes. That's the best type of advertising out there, and it's free.
Now, if you have more business then you can handle then good for you. Also, if you're trying to be exclusively "high-end" you shouldn't ever consider discounting your services, volume or not. One man operations, no way, you can't handle that many customers successfully in a short time span.
The question is, can your business use an influx of new customers? Don't worry about what "type" of customer they are. It makes no difference, their money is all the same color. The more happy customers and good work you put on the street the better it is for your business.
I think the key point is to not look at this deal as only making 25% of your normal rate but rather look at the potential that you have in impressing these new customers and essentially opening up your business to their repeat business and everyone in their Rolodex. That is the real benefit.