Even if he got that 88%, it was only after murdering is chief rival. There is also a ton of evidence of forged votes, as well as video of armed soldiers overtly looking over the shoulders of people casting their votes.
When a country is as autocratic as Russia, leaders flaunt their suppression instead of trying to hide it. Secrets hint at weakness. Brazen lies and oppression are much harder to challenge. There was almost no attempt to make the election look legitimate. The 88% is intended to remind the people that they are powerless, not to show that Putin is loved.