Disagree with OP.
ANY posting bumps a thread, there are plenty of other inane, comic, insulting or unhelpful posts that are far less useful than a HL +/- 1 statement. Do you want all that banned too? In fact why not ban people saying thanks?
HL+1 indicates thankful acknowledgement of a useful review and the kind of SP the commenter finds worth considering.
A genuine HL -1 indicates that commenter is suitably convinced by review (and other historical comment) that the SP is no longer worth chancing but also indicates SP was under consideration, again speaking to commenter's fancies.
The ridiculousness of OP's opining almost seems trollish. A quick page through the last 100 or so posts in OP's history coughs up a handful of "worthless" additions, what does he make of that?
@Kev40ish
Disingenuous statements of any kind are worthless but then how do you know which SPs are on which UKPer's HLs? The spite I have for anyone lying about any "fact" on this site far outweighs any disdain I have for a throwaway "HL-1" when the SP wasn't (yet) on a list.