Also it is very likely tugs will be deploeyd in the future to drag dead satellites back to a space station for reprocessing.
Mass does not grow on trees in the empty void of space, so reusing those is s no brainer. And the bit of noble gas your solar electric tug is gling to use up for that is negligable compared to all the effort spent to drag it all out of abgravity well or get the raw materials all they was from an asteroid, not to mention all the elaborate processing needed.
