Reid chose to miss June's Oceania Nations Cup campaign and the Olympics so he could concentrate on West Ham pre-season training.
The win sees West Ham, who won promotion from the Championship last season, move up to seventh on the table with 11 points but sees QPR firmly rooted to the bottom of the table.
Allardyce said he wasn't impressed with the Jekyll and Hyde nature of his side's effort who failed to take advantage of QPR having Samba Diakite sent off in the 75th minute.
"We showed two sides of our team," he told Sky Sports.
"The one side was the great first half we gave and completely dominated the opposition on their own ground.
"We are a newly promoted team and we have taken the game to QPR and led through two quality finishes. Let's face it it could have been more than 2-0 at half-time.
"Adel Taarabt's brilliant strike to make it 2-1 was a worry for us because it lifted the crowd and their players.
"We had to show the other side of our character, which is good honest hard work and defending. After they had a man sent off, we should really have seen the game off with more goals."
Six Kiwis have played in the Premier League - Lee Norfolk, Danny Hay, Nelsen, Simon Elliott, Chris Wood and Reid - but today's game was the first time two had played in the same game.