1. extra 400 gold which comes from SUPPORT PLAYERS early game who doesn't get any farm, result in them not able to get the wards needed

2. with the bottle crow mentality people tends to spam skills and waste the bottle, thus leaving that opening where the player is refilling the bottle with the crow and doesn't have any healing items, usually accompanied by the fact they have very low mp and/or hp left, a very dangerous move. Players that rely primarily on rune to refill bottles on the other hand plays more defensively, always saving that last charge if they can spare it, sometimes saving their lives.

3. the chances of enemy roamers killing your crow is much larger

4. The majority of the dota playing population automatically label you as a noob for using this strategy, thus preforming dota social suicide if used anywhere other than in the Philippines.

Bottle-Crow is a very pub game-friendly strat, how come? Simple.

it is a pub game player-caliber friendly strategy (if you don't like to agree, its the truth on at least the PH community). It lets one to spam for easier harassment and for creep kills ( specially when ganking is the last thing on a person's mind and being his own carry/MVP is his goal), it gives you HP replenishes as well, giving yourself allowances for someone else's damage, and since the player on your opposing lane does it as well.

Creep equilibrium is one of the player's least worries since ganks are rare, and/or somewhat predictable (play your line, proceed to the lane beside, go back to lane), making wards somewhat less valuable than they really are.

PH pubs usually has around 4 (at least?) Bottle-crow users per game, and the sad thing is that players get so used to it that they also use it on very awkward heroes (N'aix, Huskar, etc). The country's 'PRO' players are seemingly pub 'graduates' and have already maximized the potential of Bottle Crowing (scouting, rune containing/check, etc), but of course, like every strat, it still has its disadvantages.

>Bad creep equilibrium, you are likely to be spamming and thus push creeps farther away from your tower - making you more susceptible to ganks.
>Worse creep shot playing, your so-thought infinite supply to mana makes you spell trigger-happy. Timing all your skills to kill one big pool also messes up your deny. Transferring Bottle to Crow, though taking only some 1-2 seconds to transfer, burst, and array return, would also mess up your creep kills.
>Almost 1 thousand gold on early game (some 200 less if your support takes helps you) decent to high level teams using fast push strats would kill you easily.
>Entering clashes with half-empty mana bars (and possibly HP bars), with bottle away from you.
>More spams means an almost sure 15 charge stick for the opponent to use on clashes/tight situations.
>The risk of a crow dying (and possibly losing its carried items) is also there too.

disadvantages:

Let's your opponent get power ups. A mid laner with ower ups can gank your side lanes easily espcially with haste or invis.

Consumes so much gold.