The Irons beat Maltese Cup winners Birkirkara 1-0 with a scrappy 90th-minute goal from defender James Tomkins at Upton Park on Thursday night.
Should West Ham secure an aggregate victory after the second leg next week at the Ta'Qali National Stadium, then either Scottish Premiership side Inverness or FC Astra of Romania would await in round three.
While a subsequent fixture would also have to be safely negotiated before the Hammers - who entered via the UEFA Fair Play League - could take their place alongside Liverpool and Tottenham in the main draw for the group stages, Bilic understands all too well the demands placed on the squad should they deliver
"Like everything in life, it has two sides," said the former Croatia and Besiktas boss, who takes his side to Southend for a pre-season friendly on Saturday.
"The Europa League is great for the club, you could see with the spectators, they are enjoying it, against people from Andorra (in round one) and Malta, they all love to come for a European night.
"It is great for a team, it gains not confidence, but they are different types of games, so it is good for us and for me - but on the other hand, it drains you.
"I did it a few times last season, when it was great for Besiktas, but it was also very difficult to play on Thursday in Liverpool, then on the Sunday you have an away game in Turkey.
"It was the same for Tottenham to come to Istanbul, to play on a Thursday night following a three-and-a-half hour flight
They lost the game, then on Sunday they had to play at Swansea.
"That is shocking, for clubs like Borussia Dortmund, they had six games in the group stages of the Champions League, and afterwards they lost nearly all of their (German) league games, and they were down (the table).
"It has got a lot of positive things, but also a lot of negative things.
"But if you ask me, 'do I like to play in Europe?' Yes, I like it, it is good for the guys, but still we have to do a lot to qualify (for the group stages)."
Bilic is expected to rotate his squad again for their next two domestic friendlies, which include a trip to Colchester on Tuesday night before jetting off to Malta.
The likes of Cheik Kouyate and Enner Valencia could feature as they build up match fitness, while forward Diafra Sakho is suspended in Europe following his sending off in the away leg of the second round tie against Lusitans.
Summer signings Dimitri Payet and Angelo Ogbonna will also be looking to get some game time, with the new Premier League season set to start in three weeks.
Tomkins, meanwhile, felt the work-out against Birkirkara was positive, despite a largely frustrating night for the 33,048 supporters after West Ham failed to turn some 74% possession into earlier goals.
The defender said on West Ham TV: "For a lot of the boys it was their first 90 minutes, so you can't be too harsh.
"The gaffer is impressing on us how he wants to play - pass and move, and press and defend.
"It is the whole rotating system that we need to get used to and it takes a bit of time."
Source : PA
Source: PA