The metal used for the guide blocks is quite soft and sort of greasy. I'm not sure but they may be doing this to for noise, safety and or lubricity. I spray the blade and blocks with GlideCote once in a while but they still wear, more so if they are not adjusted just right. When they become notched by the blade I lap them on 220 grit silicone carbide paper with oil. The paper is cemented to a 1/2" thick glass plate (dead flat). You can do this 3-4 times before they have to be replaced.
You have to be careful with the Loctite. It comes in three strengths, Low, medium and High. Use the Low only or you will have to take a torch to the screw to loosen it. It is a great recommendation however as bandsaws do vibrate and the thrust bearing takes a lot of punishment. It is the only set screw that has come loose and there must be 10 on each guide.
If the thrust bearing becomes loose the blade will slide back in the blocks and the kerf will chew them up beyond repair.
Another factor is the quality of the blade weld. If it is stepped in any way you get thunk, thunk, thunk and this wears the guide blocks and thrust bearing faster not to mention being very annoying. A smooth running bandsaw is a thing to behold.