I didn’t know the reason behind these figures before this, but I guess I do now, since I had been coding some stuff on LUNC last few weeks.
You see, this is a superficial figure and I’ll explain why 
This is not a true representation of the apps on the chain because coders are using a function called “BroadcastTx” as the primary function for doing anything on the chain. Writing this function is faster than writing a contract and making people execute a contract. Using the BroadcastTx does the signing and sending in one transaction so all programmers are using this function instead of the ExecuteContract function.
That does NOT means that there are no apps on LUNC.
I realised this cause I used the same functions in my code also and there is no ExecuteContract in my code. Writing contracts in Rust is difficult. Much easier to use Terra.js and get something done. Only if contracts are absolutely required, do we use it.
This is a problem with Cosmos in general and how they have designed their contracts. In Cosmos coding, there are 3-4 ways of doing one thing. So, the MsgSend figures won’t give you the proper idea about the app usage.
MsgSend can be done in one step:
https://classic-docs.terra.money/docs/develop/sdks/terra-js/multisend.html
ExecuteContract is done in three steps:
https://classic-docs.terra.money/docs/develop/sdks/terra-js/smart-contracts.html