If you use a service, you contribute towards the expenses of that service.
Looking at it coldly, from a business point of view:
The typical SSPX parish was created out of thin air as an independent mass center by the parishioners. They bought the land, built the building and all of it's contents, and filled the chapel. Then they invited the SSPX in, and in exchange for a priest flying in once a week, we gave them the property and all that comes with it.
At that point, the SSPX has traded a priest for a free income property that is worth maybe $500,000, and generates an income of say $75,000 per year.
Now,
today, if a project needs to be done, should not the SSPX pay for it, if the parish can't afford it? The SSPX is holding $500,000 that they received for free from the parishioners, it's not like the SSPX is giving us anything, they are just using the money we gave them. Or is this a one way street, once the money goes in one direction, it can never go back, a type of one way valve?
To add insult to injury, now that they own the property, they throw us out.