Not all MSCs are on the Sassie format. Other platforms are ISS, Prophet and Shopmetrics. Not to mention companies using their own proprietary software such as Bestmark, Trendsource, Market Force, Stericycle and several others.
Standardizing a pay schedule is not realistic. We are independent contractors working with as many as 200 unique mystery shopping companies. Expecting them to somehow get together and decide to pay on the same schedule would be like herding cats. Some are members of the MSPA so it's conceivable they could get together to make that call. Not all are members so nothing would change for the other 50 or so companies.
Let's say the MSPA members decide to standardize. Then we have another issue, whose payment terms will be used across the board? Some pay in as little as a couple of weeks while others take three to four months. You think it is more likely to shorten terms or make them all much, much longer? In all likelihood, we would end up waiting 90 days or more. With faster pay no longer a carrot to lure in shoppers to take assignments why wouldn't the MSCs go for keeping the money in their own bank accounts as long as possible.
Equal rights for others does not mean fewer rights for you. It's not pie.
"I prefer someone who burns the flag and then wraps themselves up in the Constitution over someone who burns the Constitution and then wraps themselves up in the flag." -Molly Ivins
Never try to teach a pig to sing. It's a waste of your time and it really annoys the pig.