Rearrange the parts of the sentence in correct order.
Rewarding an encroacher on public
P-reward to a pickpocket
Q-site is like giving a
R-land with free alternative

* The opening part is "Rewarding an encroacher on public...". The word "public" needs an appropriate noun modifier, which is provided by R ("land with free alternative").
The phrase continues from R into Q ("site is like giving a").

Finally, Q connects to P ("reward to a pickpocket") to complete the simile comparison.
Therefore, the logical sequence is RQP.