In the top of the 7th, I witnessed the home team pitcher with a 7 run lead intentionally walking the inning's leadoff batter (a very good hitter, I admit). Is there any justification for this type of strategic move? If so, it escapes me.

just to piss someone off is the only reason i can think of.

I see this often done to guys who hit middle one to many times.

There is no logical explanation. The only way the team catches up is for lots of guys to reach base. He might hit a 290' fly for an out. If the ghost of Babe Ruth walks up there in that situation, pitch to him!

He was setting up for a double play.lol

The first two guys hit right on it-- it was either to piss someone off (the message sent still makes no sense) or the hitter hits middle and possibly buzzed the tower earlier in the game or has that reputation. Did he intentionally (point to first) put him on or was it the unintentional intentional walk (throw 4 pitches out of the zone badly)? I am assuming from your wording he pointed him over before the first pitch. If it's the latter, maybe he was hoping the guy would chase something to not walk and hit a bad pitch. I see that in young guy softball often-- egos too big to walk so they swing at a crap pitch and get themselves out.

As stated, you never put anyone on (especially lead off) with a lead-- you make them earn it. Nobody bats 1000.