Pacerier,
Is it proper to use 低い to mean "low salary"?
Yes it is. I hear it and see it in print all the time.
I don't agree that 低い sounds unnatural. My wife is Japanese and she agrees. You're specific example, however, (低いお給料)sounds a little unusual to me, I can't put my finger on it, but I think it's because the honorific. I've never heard that specific pairing.
If you check ALC you will find twice as many examples with 低い as with 安い。It's just a different way of saying it. As mentioned, for high salary you need to use 高い. Note that 高い means both 'high' and 'expensive' so you really have no choice there.
安い means cheap, and 低い means low. It mirrors English in that it doesn't matter whether I say "low-wages" or "cheap wages".
NOTE: you can also say お給料が少ない。 But if you find this confusing you don't need to use it, just understand if you hear it.
Or is it simply an example of usage corruption?
As above. It is not a corruption in any way. It is common. Here are samples from ALC's dictionary.
給料が低い
be ungenerously compensated
給料の低い
【形】
low-paid(仕事などが)
low-paying(仕事などが)
poorly-paid(仕事などが)
poorly-paying(仕事などが)
給料の低いパートの仕事
low-paying [low-paid, poorly-paid, poorly-paying] part-time job [work]
給料の低い仕事
low-paying [low-paid, poorly-paid, poorly-paying] job [work]
low-paying [low-paid, poorly-paid] occupation
low-paying [low-paid, poorly-paid] vocation〔log-paying occupationの方が使用頻度が高い。〕
給料の低い職業
low-paying [low-paid, poorly-paid] occupation
low-paying [low-paid, poorly-paid] vocation〔log-paying occupationの方が使用頻度が高い。〕
給料が非常に低い
be paid very little(主語の)
給料が~より低い
be paid less than(主語の)
それらの仕事は給料の面では低い。
Those jobs are in the lower echelon in terms of wages.
給料が~よりもずっと低い
get paid much less than(主語の)
支払われている給料が~よりもずっと低い
be paid much less than(主語に)
低い給料
low pay
low wage〔通例、複数形のwagesが用いられる。〕
低い給料で働く
work for a low wage
低い給料をもらう
draw low wages
さらに低い給料でより多くの責任を引き受ける
accept more responsibilities for less money
比較的低い給料
relatively-small salary
比較的低い給料を得る
earn a relatively-small salary
これまでにないほど低い額の給料をもらう
take one's lowest salary ever