And if you worked for me and I found you doing this I would fire you on the spot.
"Whereas..."? "...if you tell me..."? "...I'd give you..."?
Huh, nothing, weird. It appears you think only of negative reinforcement. So if your employees double their productivity, you offer them no reward, only threats if they seek a reward.
This leaves them with three choices:
A) Automate a process, tell you. You increase their workload to compensate. Result: Same pay, same workload, plus responsibility for the automation process.
B) Automate a process, don't tell you. Result: Same pay, decreased workload, small risk of getting caught.
C) Don't automate the process. Result: Same pay, same workload, no risk, no extra responsibility.
Logically, employees would chose between B and C, depending on their assessment of the risk of getting caught versus the benefit in halving their workload. No employee capable of automating processes would choose A unless they hadn't personally met you yet.
Meta-result: No improvements in business productivity. Low morale.
A competent business includes,
D) Automate a process, tell management. Have the increase in productivity shared. Result: Increased pay for same workload or same pay for easier workload.
Meta-result: Incentive for all employees to improve business practices. Ongoing improvements. High morale.
[I knew a guy who worked on a production line for a couple of years, suggested a single change that saved his company $1m per month in avoided waste. At the end of the year they gave him a $100 Christmas hamper. Guess how many other suggestions he shared. (Just one.)]